Missing 'Updated'

Hi. I had the structured data missing 'updated' error. I think I fixed it. I added a functions.php in my child theme. However, now I cannot view the website correctly on my phone. It just isn't formatted like it was for mobile. Should I delete the functions.php file that I created in the child theme? Can you suggest how to fix both the 'updated' error and the mobile viewing of website? http://www.thekonaproject.com